Abstract
Abstract In order to obtain information on the mechanism of ether bond formation in the synthesis of O-alkyl lipids, a study was carried out to determine if there is a loss of hydrogen from carbon 3 of dihydroxyacetone phosphate (DHAP) (non-phosphorus-linked carbon) in the course of its incorporation into glyceryl ethers. Accordingly, a mixture of [1,3-3H2] DHAP and [1,3-14C2]DHAP was prepared. In a microsomal enzyme system from Tetrahymena pyriformis which synthesizes O-alkyl lipids, it was found that there was a loss of hydrogen from carbon 3 of glyceryl ethers synthesized from double-labeled DHAP. The loss was quantitatively consistent with the labilization of one of the hydrogens linked to carbon 3 of DHAP and was not due to isomerase activity.
Highlights
In order to obtain information on the mechanism of ether bond formation in the synthesis of 0-alkyl lipids, a study was carried out to determine if there is a loss of hydrogen from carbon 3 of dihydroxyacetone phosphate (DHAP) in the course of its incorporation into glyceryl ethers
Incorporation of [I,~Hz, 1,S-W22]Dihydroxyacetone Phosphate into 0-Alkyl Lipids-The criterion for the formation of 0-alkyl lipids in this study was the chromatographic isolation of labeled glyceryl ethers and their conversion to isopropylidene derivatives
It was considered of importance to examine the products of [l, 3-3H2, 1, 3-i4Cs]DHAP incubation as compared with the products obtained after incubation of [1-i4C]hexadecanol prior to further treatment with other agents
Summary
Materials-Dihydroxyacetone phosphate, 3-phosphoglyceraldehyde, NADPH, ATP, NADH, NAD, triose phosphate isomerase (10 mg per ml), oc-glycerophosphate dehydrogenase (10 mg per ml), glycerokinase (2 mg per ml), and triethanolamine were obtained from Sigma. Ligroine (b.p. 63-75”) was obtained from Eastman. [1-i4C]Hexadecanol (25.5 mCi per mmole) was obtained from Tracerlab. 11, 3-3Hz]Glycerol (1.58 Ci per mmole, prepared by the reduction of glyceraldehyde with tritium) and [1,3-14Cz]glycerol (15.2 mCi per mmole) were obtained from. CAP, an inhibitor of triose phosphate isomerase, was prepared as described by Hartman [15]. CAP completely inhibited both triose phosphate isomerase, which was obt#ained commercially and which was present in microsomes (Fig. 1). Phosphorus analysis revealed that the CAP contained 1 atom of phosphorus per mole
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
